Balancing efficiency and safety

Balancing efficiency and safety

Blaine Hoyt, HRS Systems, Inc. explores the imperative of optimising automatic fire sprinkler systems.

Water-based suppression and control mode systems are vital in fire safety, significantly reducing loss of life and property damage. However, their effectiveness depends on the precision of their design. In designing water-based suppression systems, fire protection professionals face a paradox: the dilemma of overdesign versus under-design. Over-designed systems with larger than necessary pipes lead to inflated costs, wasted materials, and complicated maintenance, straying from sustainability and cost-effectiveness.

Conversely, under-designed systems fail to manage fire emergencies effectively, compromising safety and failing to meet standards. Here we explore the crucial balance between efficiency and safety in water-based suppression system design. It emphasises the importance of precision in avoiding over-design, ensuring sustainability, maintaining cost-effectiveness, and adhering to current and evolving fire safety standards.

Safety, cost savings and sustainability go hand-in-hand

The over-design of water-based systems involves installing systems with components, particularly pipes, that are larger than necessary for the building’s specific fire safety requirements. This might appear to be a cautious approach, but in reality, it leads to many inefficiencies and unnecessary expenditures. Over-design can stem from a conservative mindset, often driven by a fear of underperformance in critical situations. However, the ramifications of such an approach are multifaceted.

First, it significantly elevates the cost of materials. Larger pipes and additional sprinklers and/or nozzles translate to higher expenses in both procurement and installation. Additionally, oversizing a system could potentially require the structure supporting the system to be more robust than typically required for the space being protected. This increase in material usage impacts not only the project’s budget but also its timeline, as larger components can be more challenging to install, configure and obtain.

Beyond the direct financial implications, overdesigned systems also bear a substantial environmental cost. The production and transportation of additional materials contribute to increased carbon emissions. Moreover, the use of more metal and plastic, often involved in these systems, intensifies the demand for natural resources, thereby amplifying the ecological footprint of construction projects. In an era where sustainability is increasingly becoming a priority, such over-design is at odds with environmental stewardship.

From a regulatory perspective, while standards like NFPA 13 set forth requirements for water-based systems, they also emphasise the importance of efficient design with appropriate safety factors. These standards encourage the optimisation of resources to achieve the desired safety outcomes without unnecessary excess. Adhering to these guidelines ensures compliance and fosters a more balanced approach to fire safety system design.

Risks of under-designed, water-based systems

Under-designed water-based systems represent a significant concern in fire safety, carrying risks that can have far-reaching consequences. These systems, characterised by insufficient design or inadequate capacity, fail to meet the critical requirements necessary for effective fire control, posing a grave threat to both property and lives. One of the primary risks associated with underperforming systems is their inability to deliver the requisite water flow and pressure during a fire.

This deficiency can arise from several factors. These include under-sized pipes, improper placement of sprinklers, insufficient number of nozzles, inadequate water supply, or pumps that are not sized correctly. In the event of a fire, these shortcomings can lead to a system’s failure to control the flames, allowing the fire to spread rapidly and cause extensive damage. From an engineering perspective, the underperformance of a water-based system often stems from inadequate design and planning.

This can be due to a lack of understanding of the specific fire safety needs of a building, hazard, or process, errors in hydraulic calculations, or the use of substandard or inappropriate materials. Such oversights underscore the importance of rigorous design processes, thorough testing, and regular maintenance to ensure systems remain functional and effective over time.

Optimising for efficiency and safety

The optimisation of water-based systems for efficiency is a critical task that requires a meticulous approach, blending engineering acumen with a deep understanding of fire safety standards. At its core, optimisation involves refining the design to meet safety requirements without excess, thereby achieving operational and cost efficiency. A pivotal aspect of this process is conducting a thorough hydraulic analysis. This analysis centres around calculating the friction loss in the system’s pipes, which is crucial in determining the appropriate pipe sizes and layouts. The friction loss can be quantified using the Hazen-Williams equation:

where:
pm = frictional resistance (bar/m of pipe)
Qm = flow (L/min)
C = friction loss coefficient
dm = actual internal diameter (mm)

By applying this equation, professionals can identify where optimal pipe sizing will reduce costs and material use without compromising the system’s ability to control fires effectively. Optimisation also involves a comprehensive review of the layout of the suppression or control mode system.

This includes assessing the placement and spacing of sprinklers to ensure adequate coverage while avoiding redundancies. An optimal layout not only contributes to material efficiency but also enhances the system’s overall performance during a fire event.

Another key factor in optimising water-based systems is the selection of materials. Advances in materials technology have introduced more efficient options, such as lighter and more durable pipe materials, which can reduce costs and facilitate easier installation without sacrificing safety or performance.

In addition to these technical aspects, software tools play an indispensable role in system optimisation. Advanced hydraulic software like HASS allows for detailed simulations and modelling of water-based systems, providing engineers with valuable insights into how different design choices impact efficiency and effectiveness.

Hydraulic calculation software can be integrated with fire modelling packages like PyroSIM. This combination enhances our understanding of how design choices can influence fire control. These tools enable the testing of various scenarios, helping to identify the most efficient design solution that meets all safety requirements.

A well-optimised water-based system not only reduces initial installation costs but also offers long-term economic benefits. These include lower maintenance costs and potential savings in water usage during fire suppression activities. For example, increasing the branch lines and mains by one size could potentially remove the need for a pump.

This may increase the cost of the piping; but will be offset by savings from eliminating the pump and greatly reducing maintenance costs over the life of the system.

If the water-based system is more effective during a fire event it will reduce the water used during firefighting activities as well as provide additional safety for firefighters during rescue and clean-up activities. Moreover, by optimising systems to use only the necessary materials, the environmental impact of construction and operation is significantly lessened, contributing to more sustainable building practices.

Advancements in fire protection technology

The fire protection industry is continuously evolving, driven by advancements in technology that enhance the design, efficiency, and effectiveness of water-based systems. These technological innovations not only provide new solutions to traditional challenges but also open doors to more sophisticated and adaptable fire protection strategies.

One of the most significant advancements in recent years is the development of sophisticated simulation and modelling software. Hydraulic calculation and system design tools like HASS represent a leap forward in water-based suppression system design. These software solutions allow engineers to run complex hydraulic calculations and create detailed models of water-based systems, simulating various scenarios and conditions to determine the most effective designs.

They enable precise calculations of water flow, pressure requirements, and pipe sizing, ensuring that systems are optimised for both efficiency and performance. The use of these tools significantly reduces the time it takes to complete hydraulic calculations and allows designers to calculate hydraulically complicated systems, leading to more accurate and reliable outcomes.

Automated and intelligent design tools like HASS are specifically engineered to optimise safety and cost-efficiency, setting a new standard in the industry. HASS’s optimisation, powered by advanced algorithms, analyses key design parameters. It intelligently balances safety with cost efficiency, offering design options that optimise safety at minimal costs. Cutting-edge design tools, such as the HASS Optimizer, dramatically reduce the time required for system design and analysis, allowing engineers and designers to focus on other critical aspects of their projects.

Balancing efficiency, safety and sustainability in system design

The design and optimisation of water-based systems stand at a critical juncture, balancing efficiency, safety, and environmental sustainability. As we navigate through evolving technologies, regulatory landscapes, and global standards, the imperative is clear: to develop systems that are not only effective in mitigating fire hazards but also economical and eco-conscious.

The future trends in fire safety promise advancements that will further enhance this balance. Embracing these changes, while adhering to proven standards, will ensure that fire protection systems continue to safeguard lives and properties effectively in an increasingly complex and dynamic world.